Steam-boiler.



BATENTEDAUG. 27, 1907.

L. W. S. BUSLER.

STEAM BOILER.

l APPLIOATION FILED une, 1901'.

00.000 0 .Y 0 @A0 o/Awo c;

LEVI W. S. BUSLER, OF SUNBURY, PENNSYLVANIA.

STEAM-BOILER.

No. Belars.`

Specification of` Letters Patent.

Patented Aug. 27', 1907.

Applioatipn filed April 6, i907. Serial No. 366.860.

To all whom it may concern:

Be it known that I, LEVI W. S. BUsLEn, a citizen of the United States,residing at Sunbury, in the county of Northumberland and State ofPennsylvania, have invented certain new and useful Improvements inSteam- Boilers, of which the following is a specification.

The purpose of my invention is to provideimproved means for promotingthe combustion of gases from fuel in the furnaces of steam boilers, andthe invention comprises an arrangement of air feeding devices adapted tosupply air to the gases which are given off when fresh fuel is throwninto the furnace, and to hold the gases in check until they are ignitedand consumed. The air feeding tubes are arranged so that they are alwayssurrounded by water and therefore not liable to burn out, and theirarrangement is such as not to obstruct the fire box or the flue leadingtherefrom.

In the accompanying drawing which illustrates my invention, Figure l isa longitudinal central section through the boiler; Fig. 2 is a sectionthrough the flue leading from the fire box, taken on the line 2-s2 ofFig. l, and Fig. 3 is a bottom plan view of a portion of the top of thefire box or crown sheet.

Referring to the drawing, A indicates the outer shell of the boiler, inthe upper portion of which a nest of fire tubes l is arranged betweenthe tube sheets 2 and 3. The boiler has an inner shell B extending infront of the tube sheet 2 and downwardly around the fire box G and alsoaround the ue D which leads from the re box to the tube sheet 3. Apartition 4 extends from the tube sheet 3 to the vertical wall 5 of theinner shell and this partition forms the top of the re box and :flue andthe bottom of that portion of the boiler containing the fire tubes. Thetube sheet 2 is placed at some distance back ofthe vertical wall 5,about in line with the rear end of the fire box, forming a smoke box Ebetween the inner shell of the boiler and said tube sheet. The smoke boxis closed at the bottom by a partition 6, which extends between the tubesheet 2 and the verti- Cal Wall 5, and said'partition is arranged at asuitable distance above the partition 4 in order to provide a waterspace between said partitions. A stack 7 leads upwardly from the smokebox as shown. A series of air tubes 8 evenly spaced apart throughout thearea of the partition 6, extend downwardly through the partitions 6 and4, and through the intervening water space, and a Casing 9, within there box, extends over the'upper ends 0f the air tubes. A pipe l0 leadsfrom the casing 9 to an air supply pipe'll, which is connected to asuitable blower (not shown) and provided with a valve l2. By opening thevalve l2 jets of air, under pressure will be caused to flow through theair tubes 8, over the entire area of the re box, directly toward thefuel on the grate g.

Air tubes 13 and 14 extend horizontally through the front and rear wallsor water legs of the fire box, respectively, these tubes being evenlyspaced apart and located so that some of the tubes will be partlybeneath the fuel on the grate g, while the uppermost tubes will beslightly above the fuel. A casing l5 extends over ,the outer ends of thetubes 13, and this casing is conltubes 14 and this casing is connectedby a pipe 18 to the pipe 16 and thence to the pipe ll, so that when thevalve l2 is opened jets of air will be projected horizontally throughthe air tubes 13 and la into the fuel a short distance below and a shortdistance above its surface. A bridge l9 is arranged above the rear waterleg of the fire box, the rear side 19*L of said bridge being inclined,as shown, and at the rear of the bridge are arranged three series of airtubes 20, 2l and 22, which extend diagonally through the outer and innershells of the boiler and through the intervening water space. The tubes20 are arranged at the bottom of the flue and the tubes 2l and 22 arearranged at the sides of the flue. A casing 23 extends beneath the outershell of the boiler and incloses the outer ends of the three series oftubes. A pipe 25 connects the casing with the air supply pipe ll. Theair tubes 20, 2l and 22 are arranged so as to deliver jets of air intothe flue in a direction to oppose the flow of gas from the fire boxthrough the ue. An ash pan 26, hinged to the re box, extends beneath thegrate g, and a pipe 27 connected to the pipe 16 extends through anopening 28 in the ash pan so as to deliver air under pressure beneaththe grate g.

In operation when fresh fuel is thrown into the furnace through thedoorway F and the door has been closed, the valve l2 is opened, thusadmitting air through all of the air tubes, as indicated by the arrows.The air passing through the'tubes becomes intimately mixed with thesmoke and gases arising from the fuel and forces the gases downwardaround the fuel on the grate. The air flowing through the tubes 20, 21and 22 prevents the gases from fiowing through the flue D, and the airflowing through the tubes 13 and 14 mixes with the gases within andimmediately above the fuel. The from the pipe 27 passes through thegrate and upward through the fuel. The entire arrangement is such that alarge amount of air is supplied in such a manner as to become intimatelymixed with the smoke and gases, thereby supplying the necessary oxygenfor combustion of the same, and the mixed air and gases are held incheck and circulated in contact with the Y flames from the fuel, so thatcombustion of the smoke and gases which would otherwise pass out throughthe stack, takes place in the-furnace chamber and flue. After a shortinterval of time, when the newly added fuel has become heated andconditions become normal, the valve l2 is closed and the air supply shutoff; or it may be left partly open to supply any desired amount of air.

I Show-n in the drawing. YOne .purpose of the closed ash As all of theair tubes extend through the double walls of the furnace and areprotected by water, there Ais little danger ofthe tubes burning out, andthe tubes do i' not in any way obstruct the fire box or iiue. Air tubesarranged above the fire box are peculiarly liable to 'injury fromexcessive heat, and my arrangement of tubes between .the smoke box andthe fire box is particularly advantageous because the tubes aresurrounded by l water and therefore less liable to injury from heat thanthey would Abe arranged directly within the fire box.

It will, -of course, be understood that my improvements are applicableto yboilers of other forms than that pan is to prevent the smoke andgases from lbeing driven y down `through the fuel and out past the grateby the air pressure from above. The vash pan closes the `iire box belowthe grate and the pressure in the ash pan is maintained by the airadmitted `through the pipe 27.

By the 'use of my invention a large saving in fuel is effected. Whenfresh coal is thrown onto a hot fire l a large amount of the gas in thecoal -is immediately sheet extending over said -re -box and ilue, aplurality of air tubes extending horizontally through the Walls of 'there box, -a plurality of tubes extending diagonally through the walls ofthe iiue towards the throat between the fire -box and flue, ra pluralityof lair tubes extending through the crown sheet over the fire box andthrough a water 'space in the boiler, and means for conducting air tosaid tubes.

2. In 1a steam boiler, a re Ibox., ya smoke box larranged above the =rebox and sepa-rated yfrom the -c'rown sheet f.

thereof lby a water space, a plurality of air tubes extending throughthe crown sheet of the ire box and through the bottom of the smoke box,and means for conducting air to said air tubes.

3. In a steam boiler, a fire box, a smoke box arranged above the re boxand separated from the crown sheet thereof by a water space, a pluralityof air tubes extending through the lcrown sheet of the fire box andthrough the bottom of the smoke box, a casing in the re box extendingover said tubes and an air pipe leading from the interior of saidcasing.

4. In a steam boiler, a fire box and a flue extending horizontallytherefrom, said tire box and ue both having double walls withintervening water spaces, a crown sheet extending over said fire box andflue, a smoke box above said fire box and separated from the crown sheetby a water space, fire tubes above the crown sheet extending from the ueto the smoke box, a plurality of air tubes extending vertically throughthe crown sheet and the bottom' of the smoke box, a plurality -of airtubes extending -diagona-lly through the walls of the flue at the rearof the fire box and directed toward the throat between the re box andflue, a plurality of air tubes extending through the walls of thefurnace, and pipes or conduits arranged to conduct air to said tubes.

5. In a steam iboiler, a fire box and a flue extending horizontallytherefrom, said iire box and due both having double walls withintervening water spaces, a crown sheet extending over said re box andflue, a smoke box above said re `box and separated from the crown sheetby a water space, tire tubes above the crown sheet extending from theflueto the smoke box, a plurality of air tubes extending verticallythrough the crown sheet and the bottom of 'the smoke box, a plurality ofair tubes extending diagonally through the walls of the flue at the rearof the re -box and directed toward the throat between the re ybox andflue, a plurality of air tubes extending through the walls of thefurnace, casings extending over the outer ends of 'said tubes, and airpipes arranged to conduct air to the interiors of said casin'gs.

In Itestimony whereof 'I ax my signature, in Ipresence of two witnesses.

LEVI W. S. BUSLER. Witnesses:

ROBERT WATSON, NnwroN I. Winni-s.

